
The integrated area relates to temperature through the linestrength.

Linestrength is a single parameter that is typically known with lower uncertainty compared to the lineshape parameters [1]}.

The lineshape depends on the concentration of other species in the absorbing sample, and has a more complex interpretation in a non-uniform environment (e.g. the path-integrated lineshape profile along a non-uniform path departs from the traditional lineshape profiles). The complexity and uncertainty associated with lineshape models therefore make the lineshape a comparatively poor candidate measurement for inversion problems, where small measurement and model errors can produce large solution errors [2]} in the temperature distribution.

